How to get video bit depth

I have the following code:

videofile = "motion-detection.mpg";

v_object = VideoReader(videofile);

vframe_1 = read(v_object, vframe_index);

vframe_2 = read(v_object, vframe_index+1);

And I was thinking of using BitsPerPixel (v_object.BitsPerPixel), but then I'm stuck. How do I get the bit depth using the BitsPerPixel-command?

[Kshitij Chhabra]

Bit depth of a pixel is defined as the number of bits required to represent each color of the pixel, hence, the BitsPerPixel property should give you the bit depth directly.